Evaluating stereoacuity with 3D shutter glasses technology

Abstract

BackgroundTo determine the stereoacuity threshold with a 3D laptop equipped with 3D shutter glasses, and to evaluate the effect of different shape and size of test symbols and different type of disparities to stereoacuity.MethodsThirty subjects with a visual acuity in each eye of at least 0 logMAR and a stereoacuity of at least 32 arcsec (as assessed in Fly Stereo Acuity Test) were recruited. Three target symbols—tumbling "E", tumbling "C", and "□"—were displayed, each with six different sizes representing a visual acuity ranging from 0.5 to 0 logMAR when tested at 4.1 m, and with both crossed and uncrossed disparities. Two test systems were designed - fixed distance of 4.1 m and one for variable distance. The former has disparities ranging from 10 to 1000 arcsec. Each subject completed 36 trials to investigate the effect of different symbol sizes and shapes, and disparity types on stereoacuity. In the variable distance system, each subject was tested 12 times for the same purposes, both proximally and distally (the point where the 3D effect just appears and where it just disappears respectively), and the mean value was calculated from the mean proximal and distal distances.ResultsNo significant difference was found among the groups in the fixed distance test system (Kruskal-Wallis test; Chi-square = 29.844, P = 0.715). Similarly, no significant difference was found in the variable distance system (Kruskal-Wallis test; proximal: Chi-square = 5.687, P = 0.338; distal: Chi-square = 5.898, P = 0.316; mean: Chi-square = 6.152, P = 0.292).ConclusionsEvaluating stereoacuity using this measurement system was convenient and effective. Changes in target shape and size and disparity types had no significant effect on stereoacuity. It would be helpful to choose optimal targets according to different purposes using computer-assisted 3D measurements.Electronic supplementary materialThe online version of this article (doi:10.1186/s12886-016-0223-3) contains supplementary material, which is available to authorized users.

Stereoacuity measurement using a phoropter combined with two 4K smartphones

“…Stereoacuity measurement using smartphones can be performed flexibly, depending on the purpose; this is a major advantage over traditional methods of stereoacuity measurement. We can establish an equidistant stereoacuity measurement with 4K smartphones as we did using a 3D laptop equipped with shutter glasses technology . This allows us to determine stereoacuity with an accuracy of 10″ using three stepped choices, and it can reduce the deviation in clinical and research results.…”

“…Kim et al developed a contour‐based stereotest using a 3D polarisation monitor that can measure 5,000 to 20 arcseconds (″) of distance stereopsis. We also established a stereoacuity measurement system with 3D shutter glasses technology . Compared with 3D computer polarisation techniques, active shutter glasses technology can express 3D images without reducing the vertical resolution; however, observers still have to wear shutter glasses, which are uncomfortable, especially for those who have to wear corrective spectacles.…”

Stereopsis: are we assessing it in enough depth?

“…The use of digital displays allows the display of multiple levels of disparities, limited only by screen resolution at the fine end and screen width at the coarse end. As these screens are controlled by a computer, the implementation of staircase methodology can be used to automatically control the multiple levels of disparity presented using passive and active display technology, allowing the calculation of a true threshold measurement. Currently there are packages offering multiple tests of visual function, such as the ‘Thomson Software’, but these do not fully exploit the capabilities of a computer, rather they simply display a digital version of the printed test.…”

Random Dot E Stereotest underestimates stereopsis at high test distances

“…The computer ran the Windows 8.1 operating system and NVidia 3D Vision Photo Viewer was used to display 3-D images. 1 To imitate the test procedure of a Random Dot E Stereotest, we designed a picture with two parts with the same size of the original cards.…”